Propagating cherry plums from stones

Well we have had a few posts about cherry plums and related wild plums over the past few weeks. In August, Ginger and I found some trees and picked quite a haul of red, yellow and black ones. We were so pleased with the find and I brought some of the stones home with me in a bag. (And lost the bag until now!)

My query is, what would people advise I do with the stones now?
Rinse off the goo and put the stones in the fridge to stratify?
Leave the goo on and stratify?
Stratify in the fridge or the freezer?
How long for?
When to sow?
In a tray or out on the lottie?

If they germinate I will be offering baby cherry plum plants to anyone who will listen to me.